Power Conditioner

[wallawannabe]

Hey everyone,

How necessary is a power conditioner? Right now, I'm just running my G5, 002, two computer monitors, and two VLX-5's. It's kind of a lot, but I don't even have my outboard gear plugged in yet.

If it is, is it ok to just get the basic 15 amp furman (the $35 one) or should I get something beefier?

[Ethan Winer]

Originally Posted by wallawannabe

How necessary is a power conditioner?

If you don't have audible clicks and pops etc then you don't need that. However, you do need an UPS.

--Ethan

[The Byre]

There are companies that will try to persuade you that there is something wrong with the electrical supply coming into your house or studio. In particular, they will try to tell you that there are all kinds of nasty radio frequency interference (RFI) signals marching down the mains cable, bent on making everything that you record sound 'muddy' or whatever hype word they go for.

The problem (for them) is you already have several devices that are perfect at getting rid of RFI. They are called power supply units and everything has got one!

All equipment runs on direct current. The audio signal may be alternating current (AC) but all electronic equipment uses direct current (DC) internally. The great exception is the Tonwheel assembly of the original Hammond Organ that uses the AC frequency to drive an asynchronous motor invented by Larry Hammond and first used in AC-driven clocks. But that is the only exception that you will find in a modern recording studio.

The incoming AC supply (roughly 230V in Europe and 120V in the US) is turned into the desired DC voltage and current by a device called a power supply unit (PSU). Usually the incoming voltage is reduced by a transformer and then a series of rectifiers and condensers smooth out the voltage to provide the exact value required. In a so-called universal power supply, the reduction is performed by a series of thyristors, but the capacitors are still there.

These transformers and capacitors act as massive low-pass filters. Radio frequencies in the 100kHz and above stand no chance! Also, all quality equipment had little filters known as 'taps' at the beginning and end of all longer signal paths to prevent any RFI bleeding in from outside.

The upshot of all this is that even if your power supply does fall, it would have to do so by a great deal, before the PSUs in your equipment would not be able to supply the correct DC. And RFI stands no chance!

[wallawannabe]

Any advice on how to shop for a UPS? What specs should I look for?

[The Byre]

My wife has been to Indianapolis and she has assured me that it is a modern city. It is not Zimbabwe or Iraq, where you can only get elctricity now and then from a mankey, old generator out the back.

The people of Indianapolis lead realtively well-ordered and civilized lives, at least that is what my wife has told me. Of ourse, she may have been telling me tall staories and in reality, most of Indianapolis is just mud huts. Perhaps, in order to get heat, people of Indianapolis have to start a fire by rubbing two boy scouts together.

But my wife tells me that when she was working in Indianna, a well-ordered electrical supply was taken for granted. I hear you even have paved streets and traffic lights in Indianapolis!

Here in the wilds of Scotland, despite all the wind, rain and Japanese tourists, we have a very well ordered electrical supply and I have never found need for a UPS.

[FW Harper]

Balanced power always helps, theoretically. I think I would have doubts about booking a professional studio that didn't have balanced power. Equi=Tech Corporation Home Page

[wallawannabe]

Originally Posted by The Byre

My wife has been to Indianapolis and she has assured me that it is a modern city. It is not Zimbabwe or Iraq, where you can only get elctricity now and then from a mankey, old generator out the back.

The people of Indianapolis lead realtively well-ordered and civilized lives, at least that is what my wife has told me. Of ourse, she may have been telling me tall staories and in reality, most of Indianapolis is just mud huts. Perhaps, in order to get heat, people of Indianapolis have to start a fire by rubbing two boy scouts together.

But my wife tells me that when she was working in Indianna, a well-ordered electrical supply was taken for granted. I hear you even have paved streets and traffic lights in Indianapolis!

Here in the wilds of Scotland, despite all the wind, rain and Japanese tourists, we have a very well ordered electrical supply and I have never found need for a UPS.

Ha...rubbing two boy scouts together. Although your sarcasm does hurt me to my very core, you're saying I don't need a UPS?

This is confusing. I'm just gonna use AA's.

[FFTT]

Line voltage can vary quite a bit even in the most modern infratstucture.

When I test voltage before installing service to a home or business, I will very often
get readings of 243-249 volts with up to 128 volts on a single phase.

Most utilites offer some form of whole house surge protection.

I would ask your local utility if they offer this where you live.

Better safe than sorry.

I've lost an entire FX rack thanks to a lightening surge.

[The Byre]

Let me put it this way, you live in a modern city with a very good and clean power supply.

If you were to live out in the boonies, then you might need an in-line (aka on-line) UPS (uninterupted power supply) in case of a sudden black-out. This gives you full protection against brown-outs, lightning strikes, black-outs, and anything else that might come along the power cable.

However, it will only work if it is powerful enough and that means it is expensive. Check out eBay. The off-line (i.e. takes over when the power falls below a certain value or fails altogether) will protect you against power failure but does nothing for lightning strikes.

If you daisy chain about three modern surge protectors, that might provide reasonable protection against lightning strikes. Also, only use Wi-Fi for the internet. That way, any lighning strikes (or just induction) on the phone line just kills a cheap wi-fi hub and not your gear.

BUT

The most important thing you MUST do to protect your gear from damage and clean up any chance of interference, is to have a 100% ground (aka earth). Everything else is unimportant, compared to all those other Mickey Mouse things like power conditioners.

I know this is very boring and not very sexy, but grounding your equipment will do a great deal for both safety and quality of sound.

And as for balanced power - this can be dangerous and is mostly pointless.

The problem as far as balanced supplies are concerned is that under certain fault conditions it is possible to end up with half-mains voltage on the exposed metalwork.

In the US that would mean something around 60V which is not considered life threatening. In the UK it would be 120V which is definitely life threatening. That is the primary concern and why balanced supplies are not a simple or trivial solution anywhere.

The better commercial balanced supply systems have reasonably elaborate safety systems built in -- such as ground fault interrupters (GFCI) or current balance trips on each output -- but these aren't failsafe and not all boxes include them.

There are very strict regulations about the use of balanced mains systems, both in the UK and the US, and you really do need serious professional advice before contemplating their use. It is illegal to do a DIY balanced power in both countries.

And to be blunt, the benefit in improved system noise is rarely worth the conciderable financial outlay, and can usually be obtained more efficiently by correct mains and signal wiring practices, such as having a perfect earth or ground connection.

[Ethan Winer]

Originally Posted by wallawannabe

Any advice on how to shop for a UPS? What specs should I look for?

How many Watts it can provide for how many minutes.

--Ethan

[wallawannabe]

Originally Posted by The Byre

Let me put it this way, you live in a modern city with a very good and clean power supply.

If you were to live out in the boonies, then you might need an in-line (aka on-line) UPS (uninterupted power supply) in case of a sudden black-out. This gives you full protection against brown-outs, lightning strikes, black-outs, and anything else that might come along the power cable.

However, it will only work if it is powerful enough and that means it is expensive. Check out eBay. The off-line (i.e. takes over when the power falls below a certain value or fails altogether) will protect you against power failure but does nothing for lightning strikes.

If you daisy chain about three modern surge protectors, that might provide reasonable protection against lightning strikes. Also, only use Wi-Fi for the internet. That way, any lighning strikes (or just induction) on the phone line just kills a cheap wi-fi hub and not your gear.

BUT

The most important thing you MUST do to protect your gear from damage and clean up any chance of interference, is to have a 100% ground (aka earth). Everything else is unimportant, compared to all those other Mickey Mouse things like power conditioners.

I know this is very boring and not very sexy, but grounding your equipment will do a great deal for both safety and quality of sound.

And as for balanced power - this can be dangerous and is mostly pointless.

The problem as far as balanced supplies are concerned is that under certain fault conditions it is possible to end up with half-mains voltage on the exposed metalwork.

In the US that would mean something around 60V which is not considered life threatening. In the UK it would be 120V which is definitely life threatening. That is the primary concern and why balanced supplies are not a simple or trivial solution anywhere.

The better commercial balanced supply systems have reasonably elaborate safety systems built in -- such as ground fault interrupters (GFCI) or current balance trips on each output -- but these aren't failsafe and not all boxes include them.

There are very strict regulations about the use of balanced mains systems, both in the UK and the US, and you really do need serious professional advice before contemplating their use. It is illegal to do a DIY balanced power in both countries.

And to be blunt, the benefit in improved system noise is rarely worth the conciderable financial outlay, and can usually be obtained more efficiently by correct mains and signal wiring practices, such as having a perfect earth or ground connection.

So are you saying I should just plug my s*** into the wall? That's fine by me!

[The Byre]

Yes, but check that you have a 100% earth-ground.

This is easily done, get your multimeter and check the voltage between the return wire (or null) and earth-ground. If you get any reading other than 0V, sort it out or get an eletrician to do so for you.

On the two pins of your supply you should get 115V (or there abouts, an absolutely exact value is not critical) between live and earth-ground and 0V on the null or return wire.